<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        .container {
            width: 500px;
            height: 300px;
            border: 1px solid;
            display: flex;
            /* justify-content: center; */
        }

        .container>div {
            width: 100px;
            height: 100px;
        }

        .container>div:nth-child(1) {
            background-color: red;
            /* order: 1; */
        }

        .container>div:nth-child(2) {
            background-color: yellow;
            /* order: 2; */
        }

        .container>div:nth-child(3) {
            background-color: blue;
            /* order: -1; */
            align-self: ;

        }
    </style>
</head>

<body>
    <div class="container">
        <div></div>
        <div></div>
        <div></div>
    </div>
</body>

</html>